Portable, cellular phones are increasingly utilized to permit a user to communicate telephonically over a wireless system at virtually any location. The portable telephone transmits a low wattage, radio frequency signal to a receiving station, which may be connected with conventional landline telephone systems.
Portable cellular radiotelephones having two housings joined by some type of hinge that allows the housings to fold upon one another are known in the art. Some known folding radiotelephones have most of the electronics in one housing, called the body. The other housing, called the cover, normally contains fewer electronic components than the body. Other known folding radiotelephones have all the electronics in the body; thus, the cover contains no electronics.
Some known portable cellular radiotelephones utilize, as shown in FIG. 7, a hinge mechanism having a spring 742 and hinge pins 736,748 disposed in a tubular hinge arm 724 formed at an end of a cover 706, and bushings 760 formed in body 712. Spring 742 is positioned between hinge pins 736, 748, and at all times outwardly forces hinge pins 736, 748 from cover 706 to body 712. Examples of such known radiotelephones are described in PCT Publication No. WO 93/18592, published Sep. 16, 1993 and U.S. Pat. No. 5,274,882, issued Jan. 4, 1994.
Although suitable for some foldable radiotelephones, such a hinge mechanism is not suitable for all foldable radiotelephones. The known foldable radiotelephones are relatively large and have sufficient bulk and material strength to bear the spring's outwardly directed compressive forces. Further, due to their relatively large housings, small hinge elements can be readily assembled in the radiotelephone housings. Increased miniaturization of foldable radiotelephones, however, leads to more flexible housings. Consequently, their housings can deform under the spring forces exerted by known hinge mechanisms. Furthermore, the smaller housings make it more difficult to assemble the hinge elements into the smaller radiotelephone housings.
A need therefore exists for an apparatus that joins the housings of miniaturized, foldable radiotelephones.